metal Clutch Bell 26 tooth OS 91

Graupner 4448.126 Ballraced, with lining, inter-changeable
26-tooth steel pinion.
Can be used
on motors with stepped 8/9.5 mm Ø crankshaft
e.g. OS MAX 91 FX.for UNI-MECHANICS 2000 and large-capacity two-stroke motors.
reduction in noise, combined with higher power reserves compared with 61
motors. A particularly easy method of obtaining a steady, reproducible rotor speed

Other parts might be required to change gear ratios.